The present invention relates generally to a wide panel seaming method and apparatus for forming EPDM roofing membrane. More particularly, the present invention relates to a method and apparatus for continuously seaming cured stock wide panels of EPDM membrane to form a composite EPDM roofing membrane of predetermined width and indefinite length.
EPDM is used as a single ply roofing membrane material for covering industrial and commercial flat roofs. EPDM roofing membrane having a thickness between {fraction (1/16)} inch and {fraction (3/32)} inch has been found to constitute an extremely useful waterproof roofing material, particularly for industrial and commercial buildings having relatively flat roofs of very large size. Such membranes are generally applied to the roof surface in a vulcanized or cured state. Because of outstanding weathering resistance and flexibility, cured EPDM based roofing membrane has rapidly gained acceptance. Notwithstanding the wide acceptance of EPDM based roofing membrane, a disadvantage of utilizing these elastomers is the lack of adhesion of EPDM, especially cured EPDM, to itself. Application of cured EPDM roofing membrane is typically highly labor intensive because, in applying sheets of EPDM roofing membrane to a roof, it is usually necessary to splice cured sheets of EPDM roofing membrane together.
Typically, the roofing material comes in rolls and is rolled on in strips running the length of the building with a slight overlap between adjacent strips to provide a lap joint. Unfortunately, in the past such roofing material has typically been available only in rolls of relatively narrow width, for example, four feet wide. For a roof of large dimensions, such as 200 feet by 400 feet, the time required to apply the roofing material strips of narrow width becomes excessive and, in light of today""s high labor casts, relatively expensive. To reduce the application time, and hence the cost, of roofing with EPDM sheet stock, it is desirable to provide the sheet stock in rolls of very large width, such as forty feet or more wide. With sheet stock of such width, a roof measuring 200 feet by 400 feet can be applied in five 40-foot by 200-foot strips. The time required to roof a building in this manner is a mere fraction, of that previously necessary with sheet stock of narrower width, e.g., 4 feet wide. This invention relates to a method and apparatus for providing indefinite length stock of very large width synthetic rubber sheeting, e.g., EPDM membrane, from indefinite length stock of relatively narrower width.
Accordingly, it is an object of this invention to provide indefinite length sheet stock of synthetic rubber of extremely large width, e.g., forty feet or more. This object has been accomplished in accordance with certain of the principles of this invention by providing means to feed out in a horizontal direction from a feed roll or the like, a plurality of rolls of stock synthetic rubber roofing, the length being equal to the length of the desired final stock and the width being equal to the combined width of the rolls.
Briefly, according to the present invention there is provided a method of continuously seaming cured wide panels of EPDM membrane to form a composite sheet of predetermined width and indefinite length. The method includes the steps of providing at least two rolls of wide panels of cured EPDM membrane having longitudinal marginal edges and feeding the wide panels of cured EPDM roofing membranes from the at least two rolls of stock roofing membrane in a first direction. The longitudinal marginal edges of the wide panels of cured EPDM membranes are positioned in an overlapping relationship as the wide panels of cured EPDM membranes are fed in the first direction and then the overlapping longitudinal marginal edges are continuously seamed to form a composite sheet of EPDM roofing membrane of indefinite length.
The apparatus for continuously seaming wide panels of cured EPDM membrane to form a composite roofing membrane of predetermined width and indefinite length includes at least two supply stations, a seaming station and a storage station. The at least two supply stations supply and simultaneously position indefinite length stock of wide panel cured EPDM membrane in an overlapping relationship. The seaming station continuously seams the overlapping cured EPDM membranes to form a composite roofing membrane of predetermined width and indefinite length and the storage station continuously reels the composite roofing membrane for storage.